THE ASSOCIATED PRESS photo shows Rep. Max Baucus (D-Mont.), my husband, feeding our then 3 1/2-month-old son on the opening day of Congress this year, traditionally a family romp. Rep. Andy Jacobs and Rep. Martha Keys, husband and wife. Reaction to the scene, reproduced in newspapers and on TV, proves that it is all right in our society for a man to hold a baby but dangerous to the state if he gaves him any food.

Reporters called my husband's office in alarm wanting to know the age of the child, his name, but especially, why the mother wasn't with the child, and what (but why?) the mother was wearing. The administrative assistant replied, tongue in cheek, that the child was not yet named (which was true), and that I was wearing something made of blue satin and pink tulle (which was not).

The next morning Max looked up from coffee and The post and blinked: There was his child on the CBS morning news, star. The baby, who likes Hughes Rudd, didn't blink. A man whom we had met on Christmas vacation in the West Indies called that afternoon to ask how we had planted the photo, saying that my husband hadn't appeared to be that sort of person."

Then came the letters:

"I hope you spend as much time working for your constitutents as you do feeding your son," said an irate veterinarian from Conrad, Mont., enclosing a two-page list of political questions that he wanted answered immediately. "It's a cute picture but you're paid too Goddam much to babysit. Why don't stick to business?" wrote a woman from Great Falls. "If you didn't want to hear speeches, if you wanted to feed your baby, why did you run for office? You are a pretty high-priced baby sitter," a stranger in Indianapolis dashed off across the bottom of a copy from her hometown paper; she obviously never has visited the House, or else has a high tolerance for what passes for speechmaking in that chamber.

Colleagues were more charitable - Rep. Bob Cornell (D-Wis.), a priest and PH.D. who says he seldom gets such attention on the front pages at home, sent clippings and a note saying that "such publicity is grossly unfair to us celibates" - and idealists were kind. Feminists passed along the word that he mots definitely had their vote, as did militant conservative Republicans who believe that safeguarding the family is a Number One Priority.

There was even reaction from abroad. The director of Amerika Haus in Cologne, who had worked for a former Montan congressman, sent a copy of the Koelner Stadt-Anzeiger, and wrote: "It drew mention as well on the January 5 West German TV news show.' "The Nuernberger Nachricten pointed to the parliamentarian and his frau as an example of the new makeup of the U.S. Congress. An Italian newspaper commented: "It's all right to try to impress the female electorate, but maybe Baucus exaggerates a bit in order to get publicity."

Q freshman congressperson named Cavanaugh was on the floor that day, too, with one or more of his children - all redheads, at least one of whom was in a stroller. The photo of him and the stroller appeared in Time the following week. An ABC television reporter told Max later that it was too bad his child didn't have red hair, the implication being that he would have made Time that week instead of Cavanaugh. Our child, for those of you who missed him, has ligth red hair and big blue eyes. His name is Zeno Ben.